FS_BPIO_RESULTS structure (ntifs.h)

The FS_BPIO_RESULTS structure defines BypassIO operation-specific outputs for FS_BPIO_OP_ENABLE and FS_BPIO_OP_QUERY operations when a driver is failing the operation.


typedef struct _FS_BPIO_RESULTS {
  NTSTATUS OpStatus;
  USHORT   FailingDriverNameLen;
  WCHAR    FailingDriverName[32];
  USHORT   FailureReasonLen;
  WCHAR    FailureReason[128];



Receives a NTSTATUS code available to the caller that identifies why the failing driver cannot support BypassIO for this file. This field should only be set by the first driver to fail the enable/query request.


Receives the length of the string stored in FailingDriverName, in characters.


Receives a string that specifies the name of the driver that failed the request. For diagnostic reasons, a driver must store its name when it fails a FS_BPIO_OP_ENABLE or FS_BPIO_OP_QUERY operation. The name must match the actual name of the driver that is used by the system; for example, ntfs.sys. This string is not guaranteed to be NULL-terminated.


Receives the length of the string stored in FailingReason, in characters.


Receives a unique, descriptive string describing why the driver vetoed the enable/query request. This string is used for diagnostic reasons, and should be in English so that it does not need to be localized. This string is not guaranteed to be NULL-terminated.


FS_BPIO_RESULTS is returned in the FS_BPIO_OPERATIONS structure when a driver fails an enable or query BypassIO operation.

See BypassIO for filter drivers and Supporting BypassIO operations for more information.


Requirement Value
Minimum supported client Windows 11
Header ntifs.h

See also